Dysideanones F-G and dysiherbols D-E, unusual sesquiterpene quinones with rearranged skeletons from the marine sponge Dysidea avara / 中国天然药物

Four new sesquiterpene quinone meroterpenoids, dysideanones F-G (1-2) and dysiherbols D-E (3-4), were isolated from the marine sponge Dysidea avara collected from the South China Sea. The new structures were elucidated by extensive analysis of spectroscopic data including HR-MS and 1D and 2D NMR spectra, and their absolute configurations were assigned by single-crystal X-ray diffraction and ECD calculations. Anti-inflammatory evaluation showed that dysiherbols D-E (3-4) exhibited moderate inhibitory activity on TNF-α-induced NF-κB activation in human HEK-293T cells with IC50 values of 10.2 and 8.6 μmol·L-1, respectively.

Polyketide Synthases Screening from Sponge-associated Culturable Microorganisms / 微生物学通报

PKS gene was screened by PCR from thirty strains of spone-associated bacteria including twenty-one actinomycetes isolated from Craniella anstrialiensis and nine bacillus isolated from Dysidea avara in the South China Sea.As a result,a 669 bp KS domain gene was successfully amplified from Bacillus C89.BLAST analysis showed that the KS domains were most closely related to the KS sequences of Bacillus subtilis subsp.subtilis str.168 with 96% similarity.Phylogenetic analysis demonstrated the KS domain belong to trans-AT KS domains.This study demonstrated the existence of PKS gene in bacteria associated with sponge Dysidea avara for the first time,and provided proof for the hypothesis that sponge-associated bacteria are perhaps the true producers of many novel bioactive compounds in sponge.Meanwhile,this study lays a basis for the microbial screening for polyketide compounds production.

Isolation and Screening for Anti-microbial Bacteria from Sponge Dysidea avara / 微生物学通报

Sponge Dysidea avara-associated bacteria were isolated by dilution-plate method and the bacterial anti-microbial activities were screened for Escherichia coli,Staphylococcus aureu, Pseudomonas fluorescens, Bacillus subtilis,Aspergillus niger, Candida albicans,Pacecilomyces variotii by agar diffusion method.At the same time, morphology observations, biochemical and physiological identification of active strains were made. In this paper, 149 strains were isolated from sponge Dysidea avara.20 strains, which amount to 13.4% of the total isolated strains, were found to have anti-microbial activity against fungi and gram-positive bacteria and were identified to be the genus Bacillus sp.